I will assume you are looking for scale length cars. if so, Haynes MacDaniel (Mac Shops) in Florida has or had extrusions for the Baltimore and Ohio's dome sleeper and 16 and 4 sleepers, both of which were fluted Budd cars with a blue stripe at the top of a corrugated body.
Golden Gate Depot made accurate full length models of the Canadian Pacific's Budd cars that fit your description.